Intra-subject medical system, method of operating body-insertable apparatus and operative treatment

ABSTRACT

Provided is an intra-subject medical system which includes a body-insertable device and a physical quantity generator. The body-insertable device is to be introduced into a subject, is covered by a capsule-shaped exterior member, and includes a physical quantity detecting member which has a directivity to detect a predetermined physical quantity; at least one functional member which has a necessary function for examining or treating inside the subject; and a switch control unit which controls an on/off states or operation mode of the at least one functional member when the physical quantity detecting member detects a physical quantity. The physical quantity generator has a physical quantity emitting unit which emits a temporary physical quantity inside the subject; and a physical quantity direction changing unit which changes an emission direction of the physical quantity.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/655,318, filed Jan. 19, 2007, which is based upon and claims thebenefit of priority from Japanese Patent Application No. 2006-011566,filed Jan. 19, 2006, the entire contents of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an intra-subject medical system whichperforms various medical practices including examination or treatment ina body cavity in a subject, a method of operating body-insertableapparatus, and an operative treatment.

2. Description of the Related Art

Recently, in a field of endoscopes, a swallowed-type capsule endoscopehas been introduced. In such a capsule endoscope, an imaging functionand a radio communication function are provided. The capsule endoscopehas a function for moving along with peristaltic movement in a bodycavity in an internal organ such as the stomach and small intestine andsequentially taking images until it is naturally discharged from thehuman body, after swallowed by a patient though his or her mouth for theobservation (examination).

As moving in the body cavity, data of images taken by the capsuleendoscope in the human body is sequentially sent to outside by radiocommunication and stored in a memory provided in an external receiver.If the receiver including the radio communication function and memoryfunction is carried by the patient, he or she may move freely even afterswallowing the capsule endoscope and before discharging the capsuleendoscope. After that, a doctor or a nurse may give a diagnosis bydisplaying the image of the internal organ based on the image datastored in the memory.

The above-described capsule endoscope is made in a small size and alimited power source is employed. Since the electricity consumptionneeds to be minimized, a system in which the on/off states of variousfunctions in the capsule endoscope can be switched after the capsuleendoscope is introduced into a subject is disclosed in, for example,Japanese Patent No. 2849131, Japanese Patent Application Laid-Open No.2004-261240, and Japanese Patent Application Laid-Open No. 2005-73934.This turning on/off of each function is done by emitting a physicalquantity such as a magnetic field from outside and detecting thephysical quantity by a physical quantity detecting sensor provided inthe capsule endoscope, as disclosed in, for example, Japanese PatentApplication Laid-Open No. 9-143053 and Japanese Utility ModelApplication Laid-Open No. 57-187506.

However, there has been a problem that on/off states of the variousfunctions can not be surely switched, since the physical quantitydetecting sensor provided in the conventional capsule endoscope hasdirectivity.

Further, there has been a problem that the physical quantity detectingsensor of a magnetism switch or the like cannot switch an on/off statesof each function unless a physical quantity is kept being applied fromoutside of the subject so that it is difficult to maintain the on-stateof the off-state securely.

SUMMARY OF THE INVENTION

At least one object of the present invention is to solve the problems.

An intra-subject medical system according to the present inventioncomprises a body-insertable device to be introduced into a subject, thebody-insertable device being covered by a capsule-shaped exterior memberand including a physical quantity detecting member which has adirectivity to detect a predetermined physical quantity; at least onefunctional member which has a necessary function for examining ortreating inside the subject; and a switch control unit which controls anon/off states or operation mode of the at least one functional memberwhen the physical quantity detecting member detects a physical quantity;a physical quantity generator having a physical quantity emitting unitwhich emits a temporary physical quantity inside the subject; and aphysical quantity direction changing unit which changes an emissiondirection of the physical quantity.

A method of operating a body-insertable device according to the presentinvention comprises a swallowing step in which a subject swallows abody-insertable device with a function switch, in an off-state, forswitching the on/off states of each functional member including anobserving member in the body-insertable device; a switch-on step ofturning on the function switch of the body-insertable device; and acontrol step of determining whether or not the body-insertable devicehas reached a desired specific site based on an image taken by thebody-insertable device, repeating the procedure of determining whetheror not the device has reached the desired specific site by keeping thefunction switch on when the device has not reached the desiredparticular site, and turning off the function switch when the device hasreached the desired specific site.

A method of operating a body-insertable device according to the presentinvention comprises a swallowing step in which a subject swallows thebody-insertable device; a moving step of moving the subject from a farposition to a closer position to a magnet; and an on/off state controlstep of turning on a magnetic sensor in the body-insertable device andoff a function in the body-insertable device by a magnetism of themagnet.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith a function switch, in an on-state, for turning on or off functionsof various functional members including an observing member in thebody-insertable device; an observing step of observing inside of thesubject in real time with an observing function of the observing memberto specify a desired site; a switch-off step of turning off the functionswitch when the desired site is specified in the observing step; anadministration step of administering a peristalsis depressant to thesubject; a preparing step of preparing for an endoscopic surgicaloperation; a switch-on step of turning on the function switch; and atreating step of treating the desired site with reference to an imagefrom the observing member and an image from a surgical endoscope used inan endoscopic surgical operation.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith a function switch, in an on-state, of an observing member amongfunction switches for turning on or off functions of various functionalmembers including the observing member in the body-insertable device; anobserving step of observing inside of the subject in real time with anobserving function of the observing member to specify a desired site; alocking step of, when the desired site is specified in the observingstep, turning on the function switch of a locking member to lock thebody-insertable device; a switch-off step of turning off the functionswitch of the observing member; a preparing step of preparing for anendoscopic surgical operation; a switch on step of turning on thefunction switch of the observing member; and a treating step of treatingthe desired site with reference to an image from the observing memberand an image from a surgical endoscope used in an endoscopic surgicaloperation.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith a function switch, in an off-state, for turning on or off functionsof various functional members including an observing member in thebody-insertable device; a guiding step of guiding the body-insertabledevice to a desired site with a rotational magnetic field whiledetecting the position of the body-insertable device; a preparing stepof preparing for an endoscopic surgical operation; a switch-on step ofturning on the function switch; and a treating step of treating thedesired site with reference to an image from the observing member and animage from a surgical endoscope used in an endoscopic surgicaloperation.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith a first observing member, in an on-state, among function switchesfor turning on or off functions of various functional members includingthe first observing member and a second observing member in thebody-insertable device; an observing step of observing inside of thesubject in real time with an observing function of the first observingmember to specify a desired site; a preparing step of preparing for anendoscopic surgical operation; a switch on step of turning on thefunction switch of the second observing member; and a treating step oftreating the desired site with reference to an image from the first andsecond observing members and an image from a surgical endoscope used inthe endoscopic surgical operation.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith an observing member, in an on-state, among function switches forturning on or off functions of various functional members including theobserving member and a treating member in the body-insertable device; anobserving step of observing inside of the subject in real time with anobserving function of the observing member to specify a desired site; aswitch-on step of turning on the function switch of the treating member;and a treating step of treating the desired site by the treating memberwith reference to an image from the observing member.

An operative treatment according to the present invention comprises aswallowing step in which a subject swallows a body-insertable devicewith an observing member, in an on-state, among function switches ofturning on or off functions of various functional members including theobserving member and a treating member in the body-insertable device; anobserving step of observing inside of the subject in real time with anobserving function of the observing member to specify a desired site; apreparing step of preparing for an endoscopic surgical operation; aswitch-on step of turning on the function switch of the treating member;and a treating step of treating the desired site with a combination ofthe treating member and an endoscope treating member used in theendoscopic surgical operation, with reference to an image from theobserving member and an image from a surgical endoscope used in theendoscopic surgical operation.

The above and other objects, features, advantages and technical andindustrial significance of this invention will be better understood byreading the following detailed description of presently preferredembodiments of the invention, when considered in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing an outline structure of an intra-subjectmedical system according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional view showing a structure of the capsuleendoscope shown in FIG. 1;

FIG. 3 is a cross-sectional view showing a magnetic force line of amagnetic field generated by a magnetic field generating unit;

FIG. 4 is a plane view showing a magnetic force line of a magnetic fieldgenerated by the magnetic field generating unit;

FIG. 5 is a view showing an example of a transfer pathway of themagnetic field generating unit;

FIG. 6 is a cross-sectional view showing a transfer condition of themagnetic field generating unit;

FIG. 7 is a view showing an example of a template for guiding a transferpathway of the magnetic field generating unit;

FIG. 8 is a flowchart showing a procedure for turning on a functionswitch in the capsule endoscope;

FIG. 9 is a flowchart showing a procedure for turning off the functionswitch in the capsule endoscope;

FIG. 10 is a view showing an example of a pulse generated by themagnetic field generating unit;

FIG. 11 is a view showing an example of a pulse in which a pulseinterval is varied according to movement speed of the magnetic fieldgenerating unit;

FIG. 12 is a view showing an example of a pulse pattern including aswitch on/off control information;

FIG. 13 is a cross-sectional view showing a magnetic field generatingunit, in which two electrical magnets are arranged parallel to eachother;

FIG. 14 is a view showing a general structure of an intra-subjectmedical system, in which a movement of the magnetic field generatingunit is realized by an XY table;

FIG. 15 is a schematic view showing another example of a system formoving the magnetic field generating unit;

FIG. 16 is a schematic view showing another example of a system formoving the magnetic field generating unit;

FIG. 17 is a schematic view showing an example of a system forrelatively moving the magnetic field generating unit;

FIG. 18 is a schematic view showing an example of a system forrelatively moving the magnetic field generating unit;

FIG. 19 is a view showing an example in which the magnetic fieldgenerating unit is composed of a permanent magnet;

FIG. 20 is a view showing an example in which the magnetic fieldgenerating unit is composed of a permanent magnet;

FIG. 21 is a cross-sectional view showing a condition of stored magneticfield generating unit composed of the permanent magnet;

FIG. 22 is a cross-sectional view showing a condition of stored magneticfield generating unit composed of the permanent magnet;

FIG. 23 is a cross-sectional view showing the magnetic field generatingunit composed of two electrical magnets, which are arranged parallel toeach other;

FIG. 24 is a cross-sectional view showing the magnetic field generatingunit composed of two electrical magnets, which are arranged facing eachother;

FIG. 25 is a cross-sectional view showing the magnetic field generatingunit composed of two electrical magnets, which are slightly displacedfrom the positions where they face each other;

FIG. 26 is a flowchart showing a procedure for operating the capsuleendoscope when the intra-subject medical system is used for a largeintestine observation;

FIG. 27 is a diagrammatic front view showing a structure example of themagnetic field generating unit;

FIG. 28 is a cross-sectional view taken along a line A-A in FIG. 27;

FIG. 29 is a diagrammatic perspective view showing a structure exampleof the permanent magnet;

FIG. 30 is a diagrammatic perspective view showing a direction ofmagnetic field generated by the permanent magnet;

FIG. 31 is a diagrammatic perspective view showing an entire structureof a magnetic field generator 140 when not used;

FIG. 32 is a diagrammatic perspective view showing an entire structureof the magnetic field generator 140 when used;

FIG. 33 is a front view showing a magnetic field generating unit 150when used;

FIG. 34 is the front view showing a magnetic field generating unit 150when not used;

FIG. 35 is a longitudinal sectional side view showing the magnetic fieldgenerating unit 150 in FIG. 34;

FIG. 36 is a flowchart showing a procedure for operating the capsuleendoscope when the intra-subject medical system is used for a smallintestine observation;

FIG. 37 is a view showing a general structure of an intra-subjectmedical system according to a second embodiment of the presentinvention;

FIG. 38 is a view showing an example of a capsule endoscope in FIG. 37;

FIG. 39 is a view showing another example of the capsule endoscope inFIG. 37;

FIG. 40 is a view showing an example of a capsule endoscope employed ina third embodiment of the present invention;

FIG. 41 is a view showing a structure of a position detection system ofthe intra-subject medical system according to the third embodiment ofthe present invention;

FIG. 42 is a vertical sectional view showing a capsule endoscopeemployed in a fourth embodiment of the present invention;

FIG. 43 is a transverse sectional view showing the capsule endoscopeemployed in the fourth embodiment of the present invention;

FIG. 44 is a view showing a structure of a position detection system ofthe intra-subject medical system according to the fourth embodiment ofthe present invention;

FIG. 45 is a view showing an on/off state control by the positiondetection system in FIG. 44;

FIG. 46 is a view showing another example of the capsule endoscopeaccording to the fourth embodiment of the present invention;

FIG. 47 is a view showing a structure of a capsule endoscope in anintra-subject medical system according to a fifth embodiment of thepresent invention;

FIG. 48 is a view showing a structure of an example of the capsuleendoscope in the intra-subject medical system according to the fifthembodiment of the present invention;

FIG. 49 is a view showing a structure of a capsule endoscope in anintra-subject medical system according to a sixth embodiment of thepresent invention;

FIG. 50 is a view showing an on/off state control by the capsuleendoscope in FIG. 49;

FIG. 51 is a view showing a structure of a capsule endoscope in anintra-subject medical system according to a seventh embodiment of thepresent invention;

FIG. 52 is a view showing a structure of a capsule endoscope in anintra-subject medical system according to an eighth embodiment of thepresent invention;

FIG. 53 is a view showing a structure of an X-ray emission imagingdevice in an intra-subject medical system according to a ninthembodiment of the present invention;

FIG. 54 is a view showing a condition during movement of the X-rayemission imaging device in the intra-subject medical system according tothe ninth embodiment of the present invention;

FIG. 55 is a view showing a structure of a capsule endoscope in theintra-subject medical system according to the ninth embodiment of thepresent invention;

FIG. 56 is a view showing a structure of a capsule endoscope in anintra-subject medical system according to a tenth embodiment of thepresent invention;

FIG. 57 is a block diagram showing a structure of the capsule endoscopein FIG. 56;

FIG. 58 is a view showing an example of an on/off state control for thecapsule endoscope in FIG. 56;

FIG. 59 is a view showing another structure of the capsule endoscope inthe intra-subject medical system according to the tenth embodiment ofthe present invention;

FIG. 60 is a flowchart showing a procedure of a first applicationexample of the intra-subject medical system;

FIG. 61 is a view showing an outline of an endoscopic surgicaloperation;

FIG. 62 is a flowchart showing a procedure of a second applicationexample of the intra-subject medical system;

FIG. 63 is a flowchart showing a procedure of a third applicationexample of the intra-subject medical system;

FIG. 64 is a view showing a general structure of a guiding member;

FIG. 65 is a flowchart showing a procedure of a fourth applicationexample of the intra-subject medical system;

FIG. 66 is a flowchart showing a procedure of a fifth applicationexample of the intra-subject medical system;

and

FIG. 67 is a flowchart showing a procedure of a sixth applicationexample of the intra-subject medical system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Detailed description of the preferred embodiments of an intra-subjectmedical system, a method of operating body-insertable apparatus, and anoperative treatment will be described.

FIG. 1 is a view showing a general structure of an intra-subject medicalsystem according to a first embodiment of the present invention. Asshown in FIG. 1, the intra-subject medical system is introduced into asubject being tested 1 and includes a capsule endoscope 2 as abody-insertable apparatus incorporating a magnetic sensor (reed switch)3 with directivity realized by a reed switch or the like, a magneticfield generating unit 4 composed of an electrical magnet for generatinga magnetic field toward the subject 1, an arm drive unit 5 realized by amultijoint arm for moving the magnetic field generating unit 4, a viewer6 as a receiver for receiving information sent from the capsuleendoscope 2, a control unit C for controlling a magnetic fieldgeneration by the magnetic field generating unit 4 based on theinformation from the viewer 6 and the position of the magnetic fieldgenerating unit 4 and for controlling a magnetic field emissiondirection and position of the magnetic field generating unit 4 bydriving the arm drive unit 5, an input/output unit 7 connected to thecontrol unit C for inputting data to the control unit C and foroutputting data from the control unit C, and a memory 8 for storinginformation required for the control in the control unit C.

The control unit C includes a magnetic field generation controller C1, adrive controller C2 and a power distribution time controller C3. Themagnetic field generation controller C1 controls generation and stop ofgeneration of a magnetic field emitted by the magnetic field generatingunit 4. The drive controller C2 controls a drive of the arm drive unit5. The power distribution time controller C3 detects temperature by atemperature sensor 4 a disposed in the magnetic field generating unit 4and, when the detected temperature is equal to or higher than apredetermined value, reduces the power distribution time for themagnetic field generating unit 4 to prevent an increase of temperaturein the magnetic field generating unit 4. The magnetic field generatingunit 4 may change its position and the emission direction by driving thearm drive unit 5 under the control of the drive controller C2; however,the magnetic field generating unit 4 may be moved by a manual operationwith an operating unit 4 b provided in the magnetic field generatingunit 4. In this case, the amount of change at the joint portions of thearm drive unit 5 is sent to the control unit C as a movement amount.

FIG. 2 is a cross-sectional view showing a general structure of acapsule endoscope 2. As shown in FIG. 2, the capsule endoscope 2 isformed in a tubular shape having spherical ends and covered by anexterior member 10 formed in a so-called capsule shape. The exteriormember 10 accommodates an observation functional unit 12, a magneticsensor 3, a power unit 15, a data processing/control unit 16 and anantenna 17 as an observing member for emitting outside the exteriormember 10 to obtain an image. Each unit is connected by a flexiblewiring unit 18 and arranged in folds with respect to one another.

The observation functional unit 12 illuminates outside by an emittingunit 13 realized by an LED or the like through a transparent member 11formed at a part of the exterior member 10, obtains an image of theilluminated region by an imaging device 14 and sends the image to thedata processing/control unit 16. The obtained image is sent outside thesubject via the antenna 17 as image data. The data processing/controlunit 16 usually obtains two-image data in one second and sends the dataoutside the subject while the observation functional unit 12 isoperative.

The magnetic sensor 3 has directivity for detecting magnetism. When themagnetic sensor 3 is disposed vertically with respect to the axis of thecapsule endoscope, as shown in FIG. 2, the directivity directs to adirection indicated by an arrow A1. Thus, when the magnetic fieldstrength in the direction of the arrow A1 does not exceed a strengthdetected by the magnetic sensor 3, the magnetic sensor 3 does not detectthe magnetism of the magnetic field. When the magnetic sensor 3 detectsmagnetism, the data processing/control unit 16 has a function as aswitch control unit for switching the current on/off states of theobservation functional unit 12.

On the other hand, the magnetic field generating unit 4 is an electricalmagnet formed by rolling a coil around a high dielectric constantmaterial such as an electromagnetic material. As shown in FIGS. 3 and 4,the magnetic force line of the magnetic field generating unit 4 isformed so as to spread toward the whole circumference from the center ofthe axis within a surface perpendicular to an axis, which is separatedfrom the coil axis at a predetermined distance, and is gradually tiltedfrom the axis center to circumference within a surface, which includesthe axis center and is horizontal to the axis center. As a result, amagnetic force line having magnetic field directions in three dimensionwith respect to the inside of the subject can be easily formed.

The magnetic field generating unit 4 can be easily driven by the driveof the arm drive unit 5. As shown in FIG. 5, a magnetic force linehaving magnetic field directions in three dimension can be formed atevery part inside the subject 1 by moving the magnetic field generatingunit 4 in a zig-zag manner. Thus, magnetic field can be detectedwherever the capsule endoscope 2 is located in the subject. Further, asshown in FIG. 6, when the magnetic field generating unit 4 is moved in azig-zag manner along the surface of the subject 1, a greater magneticfield is emitted inside the subject 1 with smaller electricityconsumption. When the magnetic field generating unit 4 is moved by amanual operation, as shown in FIG. 7, a template 21 indicating atransfer pathway 21 a of the magnetic field generating unit 4 may berolled around the subject 1 in advance.

Here, a process of turning on and off the observation functional unit 12in the capsule endoscope 2 by the control unit C will be described withreference to flowcharts in FIGS. 8 and 9.

Firstly, a process of turning on shown in FIG. 8 is described. In thiscase, the observation functional unit 12 in the capsule endoscope 2 isassumed to be in an off-state. Upon receiving an instruction for turningon the observation functional unit 12, the magnetic field generationcontroller C1 supplies current to the magnetic field generating unit 4to generate a temporary magnetic field toward inside of the subject 1(step S101).

Then, the control unit C determines whether or not turn-on processinformation is obtained, that is, whether or not an image obtained bythe observation functional unit 12 is received from the viewer 6 (stepS102). When the turn-on process information is obtained (step S102,Yes), it means that the observation functional unit 12 is turned on, sothe process is completed.

On the other hand, when the turn-on process information is not received(step S102, No), the drive controller C2 moves the magnetic fieldgenerating unit 4 in order to change the direction of generated magneticfield (step S103), and then, the procedure goes back to step S101. Theabove procedure is repeated until the turning on process information isreceived.

Next, a process of turning off, shown in FIG. 9, is described. In thiscase, the observation functional unit 12 in the capsule endoscope 2 isassumed to be in an on-state. Upon receiving an instruction for turningoff the observation functional unit 12, the magnetic field generationcontroller C1 supplies current to the magnetic field generating unit 4to generate a temporary magnetic field inside the subject 1 (step S201).

Then, the control unit C determines whether or not turn-off processinformation is obtained, that is, whether or not the image obtained bythe observation functional unit 12 is no more received from the viewer 6(step S202). When the turning off process information is obtained (stepS202, Yes), it means that the observation functional unit 12 is turnedoff, so the procedure is completed.

On the other hand, when the turning off process information is notobtained (step S202, No), the drive controller C2 moves the magneticfield generating unit 4 in order to change the direction of the magneticfield (step S203), and then, the procedure goes back to step S201. Theabove process is repeated until the turning off process information isobtained.

Here, generation of the temporary magnetic field from the magnetic fieldgenerating unit 4 by the magnetic field generation controller C1 will bedescribed. The magnetic sensor 3 in the capsule endoscope 2 is amagnetism switch which is turned on when a magnetism equal to or greaterthan a predetermined value is detected and is turned off when amagnetism smaller than a predetermined value is detected. Thus, themagnetic field generating unit C1 generates a magnetic field withmagnetism equal to or greater than the predetermined value toward themagnetic field generating unit 4 for a predetermined period of time orlonger. When the magnetic sensor 3 is turned on for the predeterminedperiod of time or longer, the data processing/control unit 16 controlsto turn on the observation functional unit 12, even when the magneticsensor 3 is turned off. The control of the data processing/control unit16 for turning on the observation functional unit 12 is implemented whenthe observation functional unit 12 is in an off-state before the controlis implemented. Therefore, when the observation functional unit 12before controlled is in an on-state, the observation functional unit 12is turned off by the same control. That is, the on/off states of themagnetic sensor 3 and the on/off states of the observation functionalunit 12 is not associated and, when the magnetic sensor 3 is in anoff-state for the predetermined period of time or longer, the dataprocessing/control unit 16 controls the on/off states of the observationfunctional unit 12 in a toggle operation. With this structure,electricity consumption for generating magnetic field can be reduced andthe on/off states of the observation functional unit 12 can be securelymaintained.

As shown in FIG. 10, a magnetic field may be generated in a pulsedcondition. Upon detecting a magnetic field strength (magnetism strength)equal to or greater than the predetermined value, the magnetic sensor 3is turned on. Accordingly, when a magnetic field is generated in apulsed condition, the state of the magnetic sensor 3 is switched withsmaller electricity consumption, compared to a case of generating a DCmagnetic field. In particular, since the magnetism is attenuatedinversely proportional to the cube of the distance, it is very effectivethat the magnetic field is generated in a pulsed condition. However,since the magnetic field is pulsed condition, the magnetic sensor 3 isrepeatedly turned on and off at every beginning and end of the pulsedmagnetic field. Accordingly, the data processing/control unit 16controls the toggle operation of the observation functional unit 12 morethan once in a predetermined period of time when the magnetic sensor isturned on. Here, the pulse frequency is set to be equal to or less thana resonance frequency of a processing circuit (not shown) for processingoutputs of a detector of the magnetic sensor 3 and the magnetic sensor 3so that the magnetic sensor 3 is surely operated.

Further, regarding the magnetic field in a pulsed condition, when themagnetism pulse is controlled to be generated not at constant intervalsbut at intervals corresponding to a movement speed of the magnetic fieldgenerating unit 4 as shown in FIG. 11, electricity consumption can befurther reduced. In other words, when the movement speed of magneticfield generating unit 4 is fast, the intervals of pulse generation aremade smaller and, when the movement speed of magnetic field generatingunit 4 is slow, the intervals of pulse generation are made larger. Forexample, simply, when the magnetic field generating unit 4 is not moved,magnetism pulse may be generated at intervals T1 and, when the magneticfield generating unit 4 starts to be moved, magnetism pulse may begenerated at intervals T2. With this structure, variations of magneticfield density on the surface of the subject 1 are prevented, and also,electricity consumption can be reduced.

Here, as shown in FIG. 12, magnetism may be generated according to apredetermined pattern PT. The magnetic sensor 3 is turned on or off inresponse to the pattern PT. The data processing/control unit 16determines whether or not it is the predetermined pattern PT based onthe on/off states of the magnetic sensor 3 and, when it is determined asthe predetermined patter, the observation functional unit 12 iscontrolled to be in an on-state or off-state. In this case, differentpatterns are prepared for turning on the observation functional unit 12and for turning off the observation functional unit 12. The observationfunctional unit 12 can be controlled to be in a desired state regardlessof its current state. Further, in a case in which functional units otherthan the observation functional unit 12 are included, different patternsmay be prepared corresponding to each functional unit so that the on/offstates of the functional units can be controlled by the single magneticsensor 3.

Further, the above-described magnetic field generating unit 4 includes asingle electrical magnet; however, as shown in FIG. 13, two electricalmagnets may be provided. A magnetic field generating unit 24 in FIG. 13includes two electrical magnets 25, 26 which are arranged parallel toeach other so that those polar characters are arranged opposite to eachother. A loop of the magnetic force line is formed by the electricalmagnets 25, 26 and a strong magnetic field can easily be formed in adirection perpendicular to the axes of the electrical magnets 25, 26.

Furthermore, the above-described magnetic field generating unit 4 ismoved by the arm drive unit 5 of a multijoint arm; however, as shown inFIG. 14, an XY table 35 may be provided in the mounting base 30 on whichthe subject 1 lies. Here, on the XY table 35, a magnetic fieldgenerating unit 34 having the same structure as that of the magneticfield generating unit 4 may be provided, and under the control of thedrive controller C2, the magnetic field generating unit 34 may beconfigured to be moved in two dimensional directions. According to theintra-subject medical system shown in FIG. 14, the space in the mountingbase 30 is used effectively so that a system requiring a smaller spacecan be realized.

Further, the on/off states of the observation functional unit 12 in thecapsule endoscope 2 may be controlled while the subject 1 is standingup. As shown in FIG. 15, the system includes a rotary base 40 and asupport unit 41 for supporting the magnetic field generating unit 42.The magnetic field generating unit 42 moves on a vertically extendingguide 41 a of the support unit 41 to generate a magnetic field towardthe subject 1. With the combination of the up-and-down movement of themagnetic field generating unit 42 and the rotation of the rotary base40, the emission direction of the magnetic field can be varied.

The system shown in FIG. 16 is a system for emitting a magnetic field tothe subject 1 standing up. According to this system, a support unit 43which moves up and down on the guide 41 a of the support unit 41 isfurther provided so that the magnetic field generating unit 42 moveshorizontally on the horizontally-provided guide 43 a of the support unit43. Accordingly, the magnetic field generating unit 42 can be movable inthe up-and-down (vertical) direction and the horizontal direction. Inthis case, a wiggle movement of the rotary base 40 is prevented and themotionless condition of the subject 1 can be maintained more easily sothat the switching of the state the observation functional unit 12 canbe securely implemented.

According to the above-described system, the subject 1 is assumed to bemotionless and the magnetic field generating units 4, 42 are moved;however, the subject 1 may be moved to switch the state of theobservation functional unit 12 in the capsule endoscope 2 introducedinto the subject 1 while the magnetic field generating unit is keptmotionless. For example, as shown in FIG. 17, a rotary base 50 forrotating the subject 1 who is standing up and a support unit 51 forfixing a magnetic field generating unit 52 and movably supporting therotary base 50 may be included and the rotary base 50 may be moved on aguide 51 a provided on the support unit 51 to put the subject 1 close tothe magnetic field generating unit 52.

Further, as shown in FIG. 18, the system may include a tubular shapedmagnetic field generator 61 and a mounting base 60 for mounting thesubject 1 and a magnetic field may be emitted to the subject 1 byinserting/removing the mounting base 60 into/from the magnetic fieldgenerator 61. In this case, the mounting base 60 is preferably rotatableabout the axis of inserting and removing direction.

The magnetic field generating units 4, 34, 42, 52 and the magnetic fieldgenerator 61 are realized by an electrical magnet or a magnet coil;however, the present invention is not limited to this and a permanentmagnet may be employed to generate a magnetic field. However, when apermanent magnet is employed, since the permanent magnet constantlygenerates a magnetic field, a measure for the case the magnetic field isnot used is needed.

For example, as shown in FIG. 19, the circumference of the permanentmagnet 74 is covered by a nonmagnetic resin 72 and connected to the armdrive unit 5 via a base unit 70 made of a ferromagnetic material. Withthis structure, a magnetic field generating unit using a permanentmagnet 74 can be realized. When the magnetic field is not used, themagnetic field generating unit is covered by a casing unit 76 made of aferromagnetic material from an end of the magnetic field generating unitto cover the permanent magnet 74 with the base unit 70 and the casingunit 76 made of an electromagnetic material so as to reduce leakage ofthe magnetic field. In FIG. 19, a spacer 75 is disposed inside thecasing unit 76.

Further, as shown in FIG. 20, a casing unit 86 corresponding to thecasing unit 76 may be provided to the arm drive unit 5 in advance. Inthis case, a resin 82 includes a guide for guiding the casing unit 86 sothat the casing unit 86 moves on the guide to block the magnetic fieldwhen the magnetic field is not used. The casing unit 86, shown in FIG.20, is not required to cover the whole circumference of the permanentmagnet 84 and may be provided so as to block the magnetic force line ofthe permanent magnet 84.

Furthermore, as shown in FIG. 21, a permanent magnet 94 may be removablyattached to an end of the arm drive unit 5 and stored in a box 90 madeof a ferromagnetic material when the magnetic field is not required. InFIG. 21, a support unit 93 made of a nonmagnetic resin is provided inthe bottom of the box 90, which has an opening in its upper portion andis made of a ferromagnetic material. The permanent magnet 94 is disposedon the support unit 93 and the opening of the box 90 is covered by acover unit 91, which is made of a ferromagnetic material and has asupport unit 92 made of a nonmagnetic resin on its bottom surface. Thepermanent magnet 94 includes a gripper 95 for moving the permanentmagnet 94. Further, the permanent magnet 94 is not required to bedisposed at an end of the arm drive unit 5 and may be held by anoperator to be put closer to the subject 1 to generate a magnetic fieldinside the subject. As shown FIG. 22, a cover unit 101 and a box unit100 may be separatably provided.

Further, when a magnetic field generating unit is provided with apermanent magnet, as shown in FIG. 23, two permanent magnets may bearranged in parallel in order to generate a strong magnetic field. Forexample, as shown in FIG. 23, two permanent magnets 114, 115 arearranged parallel to each other so that those polar characters arearranged opposite to each other at a face of a support unit 110 made ofa ferromagnetic material and each circumference of the permanent magnets114, 115 is covered by a nonmagnetic resin 111. In this magnetic fieldgenerating unit, also, a cover unit 116, which is made of aferromagnetic material and has a gripper 117 is provided on the otherside of the support unit 110 so as to sandwich the permanent magnets114, 115 in order to reduce leak of the magnet field when the magnetfield is not used. In this case, a magnetism circuit, in which themagnetic force line forms a closed loop, is generated by the permanentmagnets 114, 115, the cover unit 116 and the support unit 110 andleakage of the magnetic field can be prevented.

Further, when the magnetic field generating unit is realized by apermanent magnet, as shown in FIG. 24, the permanent magnets 124, 125may be arranged opposite while sandwiching the subject 1. In this case,when a member for supporting the permanent magnets 124, 125 is made of aferromagnetic material, a magnetism circuit is formed and leakage of themagnetic field can be prevented. As shown in FIG. 25, the permanentmagnets 134, 135 may be displaced from the positions where they faceeach other. This oblique arrangement may provide a blank space aroundthe size of the subject 1. In each of the cases, the subject 1 is placedon the magnetism circuit.

A method of using the intra-subject medical system will be described.Firstly, a method of using the system to observe the large intestinewill be explained with reference to FIG. 26. As shown in FIG. 26, thefunctional units including the observation functional unit 12 of thecapsule endoscope 2 are turned off and swallowed by a person to beexamined (step S301). Then, a digestant for promoting digestion isadministered to accelerate the movement of the capsule endoscope 2 (stepS302). Then, it is determined whether or not a predetermined period oftime has elapsed (step S303), and, only when the predetermined period oftime has elapsed (step S303, Yes), a process of turning on isimplemented to turn on the function switch in the capsule endoscope 2(step S304, See FIG. 8). An image sent by the capsule endoscope 2 isreceived (step S305) and it is determined whether or not the image is animage showing the large intestine (step S306). When the large intestineis not shown in the image (step S306, No), an process of turning off isimplemented to turn off the function switch in the capsule endoscope 2(step S307, See FIG. 9), and then, the procedure goes back to step S302to repeat the above procedure. On the other hand, when the largeintestine is shown in the image (step S306, Yes), the procedure ends. Inthis condition, the capsule endoscope 2 in the large intestine movescorresponding to peristaltic movements of the large intestine andsequentially takes images in the large intestine to send the imagesoutside the subject 1. In this way, the large intestine can be observed.

Here, a magnetic field generator composed of a magnetic field generatingunit, a magnet housing unit, an elevating unit and the like will bedescribed as a more detailed example of a magnetic field generator usinga permanent magnet. FIG. 27 is a diagrammatic front view showing astructure example of the magnetic field generating unit and FIG. 28 is across-sectional view taken along a line A-A in FIG. 27. A magnetic fieldgenerating unit 150 has its lower portion in a taper shape so as to beeasily stored in a magnet housing unit and includes a permanent magnet151 therein. The permanent magnet 151 is, as shown in FIG. 29, composedof five blocks 151 a to 151 e which are integrally combined in a Vshape. Thick arrows in FIG. 29 indicate magnetization directions of eachblock 151 a to 151 e. FIG. 30 shows a direction of magnetic fieldgenerated by the permanent magnet 151 composed as described above.Dashed lines indicate directions of a main magnetic field and thinarrows indicate directions of magnetic field on a plane surface.According to the example shown in FIG. 30, a magnetic field at aposition A is generated in a direction x, a magnetic field at a positionB is generated in direction y and a magnetic field at a position C isgenerated in a direction z.

With such a magnetic field generating unit 150, a magnetic fieldrequired for switching operation can be generated in all directions x, yand z at a position on a plane surface, which is separated from a frontsurface of the magnetic field generating unit 150 by a predetermineddistance d. Further, as shown in FIG. 29, magnetization directions ofeach block 151 a to 151 e are set so that magnetic field generatedtoward back side (the direction of -z) can be reduced. Further, as shownin FIG. 28, the magnetic field generating unit 150 includes a magneticmaterial 152 formed in a same V shape as the permanent magnet 151 behindthe permanent magnet 151 via a nonmagnetic material 153 so as to furthersuppress the magnetic field leakage behind the permanent magnet 151. Thenonmagnetic material 153 covers the whole circumference of the permanentmagnet 151. As shown in FIGS. 27 and 28, above the magnetic fieldgenerating unit 150, a cover 156 composed of the magnetic material 154and the nonmagnetic material 155 is provided. Behind the magnetic fieldgenerating unit 150, a connection arm 157 is connected.

FIG. 31 is a diagrammatic perspective view showing an entire structureof a magnetic field generator 140 which is not in use and FIG. 32 is adiagrammatic perspective view showing an entire structure of themagnetic field generator 140 which is in use. The magnetic fieldgenerating unit 150 is fixed to an elevating unit 141 of the magneticfield generator 140 by the connection arm 157. The magnetic fieldgenerating unit 150 can be moved upward and downward via a chain 143 byoperating an elevating handle 142. Further, when the magnetic fieldgenerating unit 150 is moved downwardly, the magnetic field generatingunit 150 is configured to be contained in a magnet housing unit 145having casters 144.

Here, a relationship between the magnetic field generating unit 150 andthe magnet housing unit 145 will be described with reference to FIGS. 33to 35. FIG. 33 is a front view showing a magnetic field generating unit150 when used, FIG. 34 is a front view showing the magnetic fieldgenerating unit 150 when not used, and FIG. 35 is a longitudinalsectional side view of the magnetic field generating unit 150 in FIG.34. The magnetic field generating unit 150 is contained in the magnethousing unit 145 with a space therearound and the cover 156 is formed soas to overlap the upper end of the magnet housing unit 145. Further, asshown in FIG. 35, when the magnetic field generating unit 150 iscontained in the magnet housing unit 145, the magnetic material 146formed in the same shape as the permanent magnet 151 is arranged infront of the permanent magnet 151 via a nonmagnetic material 147, and amagnetic material 148 and a nonmagnetic material 149 are alternativelydisposed around these elements so as to reduce leakage of the magneticfield from the magnetic field generating unit 150.

Next, a method of using the system to observe the small intestine willbe described with reference to FIG. 36. In FIG. 36, firstly, functionalunits including the observation functional unit 12 in the capsuleendoscope 2 is turned off and swallowed by a person to be examined (stepS401). Then, it is determined whether or not a predetermined period oftime has elapsed (step S403), and, only when the predetermined period oftime has elapsed (step S402, Yes), a process of turning on isimplemented to turn on the function switch in the capsule endoscope 2(step S403, See FIG. 8). An image sent by the capsule endoscope 2 isreceived (step S404) and it is determined whether or not the image is animage showing the small intestine (step S405). When the small intestineis not shown in the image (step S405, No), a process of turning off isimplemented to turn off the function switch in the capsule endoscope 2(step S406, See FIG. 9), and then, the procedure goes back to step S402to repeat the above procedure. On the other hand, when the smallintestine is shown in the image (step S405, Yes), the procedure iscompleted. In this condition, the capsule endoscope 2 in the smallintestine moves corresponding to peristaltic movements of the smallintestine and sequentially takes images in the small intestine to sendthe images outside the subject 1. In this way, the large intestine canbe observed.

It is noted that, in the first embodiment, the control of the on/offstates of the observation functional unit 12 has mainly been described;however, the present invention is not limited to this and is applied toan on/off state control of each functional units when one or morefunctional units including a biopsy function, a medication function, ahemostatic function, a cauterization function and a marking function ofthe capsule endoscope 2. Further, in addition to the functional units,the present invention may be applied to an on/off state control of apart of functions of a radio transmission processing unit or the dataprocessing/control unit 16. Further, the present invention may beapplied to on/off state controls of not only objective functions butalso general functions such as a locking function.

Next a second embodiment of the present invention will be described.According to the first embodiment, the magnetic field emission directionof the magnetic field generating unit 4 is controlled based on theinformation that is sent from capsule endoscope 2 and obtained by theviewer 6; however, according to the second embodiment, the magneticfield emission direction of the magnetic field generating unit 4 iscontrolled based on a position of the capsule endoscope 2.

FIG. 37 is a view showing a structure of an intra-subject medical systemaccording to the second embodiment of the present invention. Compared tothe intra-subject medical system of FIG. 1, this intra-subject medicalsystem further includes a metal detector 204 for detecting the positionof the capsule endoscope 2 by detecting the metal inside the capsuleendoscope 2 such as a battery, an arm drive unit 205 for moving themetal detector 204 and a position detector C4 for detecting the positionof the capsule endoscope 2 based on a detection result of the metaldetector 204. The magnetic field generation controller C1 and the drivecontroller C2 control the magnetic field generation and emissiondirection of the magnetic field based on position information detectedby the position detector C4. Since the position of the capsule endoscope2 is already known, the region where the magnetic field generating unit4 is moves is reduced and switching is implemented more quickly.

Here, as shown in FIG. 38, the capsule endoscope 2 preferably includes amagnetic sensor 3 so as to have directivity of detecting sensitivity inan axial direction of the capsule endoscope 2 and a conductive plate 210having a face perpendicular to the detection sensitivity direction ofthe magnetic sensor 3. The metal detector 204 generates an eddy currenton an conductive face of the conductive plate 210 and detects amagnetism generated by the eddy current. Accordingly, directivity isgenerated in a detection sensitivity of the metal detector 204 bycreating a direction that generates a large eddy current by theconductive plate 210. As a result, the metal detector 204 recognizesthat the axis of the capsule endoscope 2 is in a direction perpendicularto the direction of the large detection sensitivity so that a directionof the capsule endoscope 2 as well as the position of the capsuleendoscope 2 can be detected. Thus, the region where the magnetic fieldgenerating unit 4 is moved is further reduced and switching can beimplemented more quickly.

Further, as shown in FIG. 39, when the detection sensitivity directionof the magnetic sensor 3 is perpendicular to the axial direction of thecapsule endoscope 2, the conductive face of the conductive plate 211 maybe disposed perpendicular to the axial direction of the capsuleendoscope 2.

It is noted that the conductive plates 210, 211 can be realized by aparamagnetic metal such as aluminum or copper that easily generates aneddy current.

Next, a third embodiment of the present invention will be described.According to the second embodiment, the conductive plate and metaldetector are used for detecting the position of the capsule endoscope 2;however in the third embodiment, an LC marker is employed to detect theposition of the capsule endoscope 2.

As shown in FIG. 40, an LC marker 220 is provided in the capsuleendoscope 2. The LC marker 220 is a resonance circuit connected to acoil and a condenser, receives an external alternate magnetic field inresonance frequency with the coil and generates an external alternatemagnetic field from the coil by induced current accumulated in thecondenser. In this case, the coil of the LC marker 220 has a directivityof magnetic field generation, so the direction of the capsule endoscope2 as well as the position of the capsule endoscope 2 can be detected.

FIG. 41 is a view showing a structure of a position detection systemusing the LC marker 220. As shown in FIG. 41, the position detectionsystem includes a drive coil 231 for generating an alternate magneticfield toward the LC marker 220 and a sense coil group 232 detecting thealternate magnetic field generated by the LC marker 220. The drive coil231 and the sense coil group 232 are disposed on a surface of thesubject 1. The position detector C4 includes a signal generating unitC41 for sending an alternate signal for instructing the drive coil 231to generate an alternate magnetic field and a position calculator C42for calculating the position of the capsule endoscope 2 based on thealternate magnetic field strength received by each sense coils 232 a to232 f. The position calculated by the position calculator C42 is usedfor controlling movement of the magnetic field generating unit 4 or thelike and, in this case, the calculated position may be output on adisplay unit 237, which is a part of the input/output unit 7.

According to the third embodiment using the LC marker 220, since poweris not required by the LC marker 220, the position and direction of thecapsule endoscope 2 can be detected even when the function switch of thecapsule endoscope 2 is in an off-state.

Next, a fourth embodiment of the present invention will be described.According to the above-described second and third embodiments, theregion where the magnetic field generating unit 4 is moved is reducedand switching is implemented quickly by detecting the position of thecapsule endoscope 2; however, in the fourth embodiment, the direction ofthe capsule endoscope 2 is controlled and a magnetic field is emitted tothe direction-controlled capsule endoscope 2.

As shown in FIG. 42, the capsule endoscope 2 includes the magneticsensor 3 along the axis of the capsule endoscope 2 and the magnetismdetecting direction of the magnetic sensor 3 is directed parallel to theaxis. Inside the capsule endoscope 2, a disk-shaped permanent magnet 240for generating a magnetic field perpendicular to the axis and thesurface of the permanent magnet 240 is placed perpendicular to the axis.On the other hand, a magnetic field generating unit 251 for generating amagnetic field in a direction Z, a magnetic field generating unit 252for generating a magnetic field in a direction Y and a magnetic fieldgenerating unit 253 for generating a magnetic field in a direction X aredisposed around the subject 1. The subject 1 is placed on the mountingbase 250 and its longitudinal direction is in the direction X.

As shown in FIG. 45, the magnetic field generating unit 251 generates amagnetic field to the subject 1 prior to the magnetic field generatingunits 252, 253 and when the longitudinal direction of the permanentmagnet 240 directs the direction of the generated magnetic field, theaxis of the capsule endoscope 2 is placed on the X-Y surface. That is,the magnetism detecting direction of the magnetic sensor 3 is placed onthe X-Y surface. At a timing t1 as maintaining the magnetic fieldgeneration of the magnetic field generating unit 251 and the directionof the capsule endoscope 2, the magnetic field generating units 252, 253emit temporary magnetic fields in the directions X and Y. With this, themagnetic sensor 3 is surely tuned on and the on/off state control of thefunction switch can be surely implemented.

As shown in FIG. 46, the magnetic sensor 3 may be disposed so as to havea magnetism detecting direction perpendicular to the direction of themagnetic field generated by the permanent magnet 260 having the samestructure and arrangement as the permanent magnet 240, that is, theaxial direction of the capsule endoscope 2.

Next, a fifth embodiment of the present invention will be described.According to the above-described fourth embodiment, the magnetic sensoris turned on by controlling the direction of the capsule endoscope 2;however, in the fifth embodiment, an optical sensor 272 is employed as asubstitute for the magnetic sensor 3.

As shown in FIG. 47, in the intra-subject medical system of the fifthembodiment, similar to the fourth embodiment, a permanent magnet 261 forcontrolling the posture is provided in the capsule endoscope 2. Similarto the fourth embodiment, the permanent magnet 261 is a flat platforming a flat surface perpendicular to the axial direction of thecapsule endoscope 2 and the magnetic field is perpendicular to the flatsurface. The capsule endoscope 2 further includes an optical sensor 272as a substitute for the magnetic sensor 3. The optical detectingdirection of the optical sensor 272 is the same as the direction of themagnetic field of the permanent magnet 261. On the other hand, themagnetic field generating unit 4 includes an optical generating unit 271such as an LED on its end. When an on/off state control of theobservation functional unit 12 in the capsule endoscope 2 isimplemented, similar to the electrical magnet 251, a magnetic field isemitted from the magnetic field generating unit 4 to the subject 1 andthe permanent magnet 261 is operated so as to change the posture of thecapsule endoscope 4. In such condition, infrared light, for example, isemitted from the optical generating unit 271 to turn on the opticaldetector 272. In this case, according to the relation of the posture ofthe capsule endoscope 4 and the position of the magnetic fieldgenerating unit 4, the optical generating unit 271 and the opticaldetector 272 are facing each other and the optical detector 272 cansurely be turned on. Based on the transfer to the on-state of theoptical detector 272, the data processing/control unit 16 controls theon/off states of the functions in the observation functional unit 12.

As shown in FIG. 48, a permanent magnet 262 may be provided as asubstitute for the permanent magnet 261. The permanent magnet 262 iscomposed of layered disk-shaped North pole and South pole and disposedso that its flat face is perpendicular to the axis of the capsuleendoscope 2. Further, an optical detector 282 having optical detectingdirection in the axial direction of the capsule endoscope 2 is providedas a substitute for the optical detector 272. With such structure, theoptical generating unit 271 and the optical detector 282 are faced eachother so that the optical detector 282 can surely be turned on.

Next, a sixth embodiment of the present invention will be described.According to the fourth embodiment, the magnetic sensor is turned on bycontrolling the direction of the capsule endoscope 2; however, in thesixth embodiment, a conductive plate is provided as a substitute for thepermanent magnet to control the direction of the capsule endoscope 2.

In other words, as shown in FIG. 49, the magnetic sensor 3 is disposedso that the magnetic field detecting direction of the magnetic sensor 3is perpendicular to the axis of the capsule endoscope 2 and adisk-shaped conductive plate 290 formed by metal such as aluminum orcopper is provided. In this case, a plate surface of the conductiveplate 290 is disposed perpendicular to the axis of the capsule endoscope2.

When the on/off state control of the observation functional unit 12 inthe capsule endoscope 2 is implemented, firstly as shown in FIG. 50, analternate-current magnetic field S1 of several tens of kHz is generatedfrom the magnetic field generating unit 304. On the conductive plate290, an eddy current corresponding to the alternate-current magneticfield is generated and the conductive plate 290 is magnetized by theeddy current.

Accordingly, since the alternate-current magnetic field of the magneticfield generating unit 304 and the magnetic field of the conductive plate290 are synchronized, the direction of the capsule endoscope 2 iscontrolled by the direction of the magnetic field of the magnetic fieldgenerating unit 304. In such condition, the a temporary magnetic fieldS2 is emitted, for example, from the magnetic field generating unit 4,in a direction perpendicular to the axis of the capsule endoscope 2.With this, the magnetic sensor 3 is turned on and, based on the transferto the on-state of the magnetic sensor 3, the data processing/controlunit 16 controls the on/off states of the functions of the observationfunctional unit 12.

The resonance frequency of the magnetic sensor 3 is set smaller than thefrequency of the alternate-current magnetic field generated by themagnetic field generating unit 304 (see FIG. 50). With such setting, achattering of the magnetic sensor 3 generated by the alternate-currentmagnetic field can be prevented.

Next, a seventh embodiment of the present invention will be described.According to the fourth embodiment, the magnetic sensor is turned on bycontrolling the direction of the capsule endoscope 2; however, in thesixth embodiment, a ferromagnetic material bar is provided as asubstitute for the permanent magnet to control the direction of thecapsule endoscope 2.

In other words, as shown in FIG. 51, the magnetic sensor 3 is disposedso that the magnetic field detecting direction of the magnetic sensor 3is to be the axial direction of the capsule endoscope 2 and aferromagnetic material bar 300 is provided, whose longitudinal directionis to be perpendicular to the axis of the capsule endoscope 2.

When controlling the on/off states of the observation functional unit 12in the capsule endoscope 2, firstly, a magnetic field is generated fromthe magnetic field generating unit 304 to the subject 1. Theferromagnetic material bar 300 is magnetized by the magnetic fieldemitted by the magnetic field generating unit 3 and the posture of thecapsule endoscope 2 is controlled so that the longitudinal directiondirects in the same direction of the magnetic field direction. In suchcondition, a temporary magnetic field is emitted from, for example, themagnetic field generating unit 4 in the axial direction of the capsuleendoscope 2. With this, the magnetic sensor 3 is turned on and, based onthe transfer to the on-state of the magnetic sensor 3, the dataprocessing/control unit 16 controls the on/off states of the functionsof the observation functional unit 12. Since the ferromagnetic materialbar 300 does not generate magnetism, the magnetic sensor 3 and theferromagnetic material bar 300 may be arranged closed to each other inthe capsule endoscope 2. Accordingly, the design of the capsuleendoscope 2 becomes more flexible.

Next, an eighth embodiment of the present invention will be described.According to the first embodiment, the on/off states of the observationfunctional unit 12 is controlled by the magnetic sensor 3; however, inthe eighth embodiment, a temperature sensor, as a substitute for themagnetic sensor 3, for detecting a heat generated by a magnetism toindirectly detect the magnetism.

In other words, as shown in FIG. 52, a heat generator 310 for generatingheat by an induction heating and a temperature sensor 311 for detectingthe temperature resulting from the heat generated by the heat generator310 are provided in the capsule endoscope 2. When an alternate-currentmagnetic field is emitted from the external magnetism generating unit304, the heat generator 310 generates heat according to the magneticfield strength and the temperature sensor 311 detects the temperatureresulting from the heat. When the temperature becomes equal to orgreater than a predetermined value, the data processing/control unit 16controls the on/off states of the observation functional unit 12.

Next, a ninth embodiment of the present invention will be described.According to the first embodiment, the on/off states of the observationfunctional unit 12 is controlled by the magnetic sensor 3; however, inthe eighth embodiment, an X-ray is used as a physical quantity and whenan X-ray sensor disposed in the capsule endoscope detects an X-ray, theon/off states of the observation functional unit 12 is controlled.

FIGS. 53 and 54 are views showing general structures of the ninthembodiment of the present invention, and FIG. 55 is a view schematicallyshowing structure of a capsule endoscope according to the ninthembodiment of the present invention. In FIG. 53, the intra-subjectmedical system includes an X-ray emission imaging device 330. The X-rayemission imaging device 330 includes an X-ray emitting unit 331 and anX-ray receiving unit 332 which are arranged facing each other. As shownin FIG. 54, the facing X-ray emitting unit 331 and an X-ray receivingunit 332 can be rotated and moved while maintaining the positionalrelationship. Further, a mounting base 320 is provided so that thesubject 1 is placed between those facing X-ray emitting unit 331 and anX-ray receiving unit 332.

When the on/off states of the observation functional unit 12 in thecapsule endoscope 2 is controlled, firstly, a weak X-ray is emitted fromthe X-ray emitting unit 331 to the subject 1 and an X-ray image of thecapsule endoscope 2 is obtained. Then, the X-ray emitting unit 331 andan X-ray receiving unit 332 are moved to emit the weak X-ray to thesubject 1 from a different direction and an X-ray image of the capsuleendoscope 2 is obtained. The position and posture of the capsuleendoscope 2 are calculated based on the two X-ray images. According tothe calculated position and posture, the X-ray emitting unit 331 and anX-ray receiving unit 332 are moved and a strong X-ray is temporarilyemitted from, for example, the axial direction of the capsule endoscope2 and the X-ray sensor 340 in the capsule endoscope 2 is securely turnedon. Based on the transfer to the on-state of the X-ray sensor 340, thedata processing/control unit 16 controls the on/off states of theobservation functional unit 12.

As shown in FIG. 55, the X-ray sensor 340 is disposed so as to havesensitivity in the axial direction of the capsule endoscope 2. The X-raysensor 340 is composed of an X-ray sensor having sensitivity in an axialdirection and an X-ray sensor having sensitivity in another axialdirection and those sensors are arranged back-to-back. Accordingly theX-ray sensor 340 is configured to surely detect X-rays emitted in eitherone of the axial directions.

Next, a tenth embodiment of the present invention will be described.According to the first to ninth embodiments, a single physical quantitydetecting member such as a magnetic sensor is provided; however, in thetenth embodiment, a plurality of physical quantity detecting members areprovided to control the on/off states of a plurality of observationfunctional units.

FIG. 56 is a schematic view showing a general structure of a capsuleendoscope according to a tenth embodiment of the present invention. FIG.57 is a block diagram showing a structure, in the capsule endoscope inFIG. 56, for controlling an on/off states of an observation functionalunit. FIG. 58 is a view showing a relationship between an externalmagnetic field strength and on/off states when the on/off states of twoobservation functional units are controlled by an external magneticfield.

In FIGS. 56 to 58, the capsule endoscope 402 includes therein twoobservation functional units A, B, observation control units 413 a, 413b for controlling on/off states of the observation functional units A,B, and two magnetic sensors 403 a, 403 b. The magnetic sensor 403 a is amagnetism switch turned on or off by a weak magnetic field strength Pth2and the magnetic sensor 403 b is a magnetism switch turned on or off bya magnetic field Pth1 which is greater than the magnetic field strengthPh2. Other structures are the same as those of the intra-subject medicalsystem shown in FIG. 1.

A procedure of selectively controlling an on/off states of one of orboth of the observation functional units A, B in the capsule endoscope 2will be described. In the tenth embodiment, the on/off states of themagnetic sensor is the same as the on/off states of the observationcontrol units 413 a, 413 b. Firstly, in order to switch both of theobservation functional units A, B from an off-state to an on-state, amagnetic field greater than the magnetic field strength Pth1 is emittedfrom the magnetic field generating unit 4. In order to switch only theobservation functional unit A from an off-state to an on-state, amagnetic field smaller than the magnetic field strength Pth1 and greaterthan the magnetic field strength Pth2 is emitted from the magnetic fieldgenerating unit 4. In order to switch only the observation functionalunit B to an on-state, a magnetic field greater than the magnetic fieldstrength Pth1 is emitted to turn on both of the observation functionalunits A, B, and then, a magnetic field smaller than the magnetic fieldstrength Pth1 and greater than the magnetic field strength Pth2 isemitted to turn off the observation functional unit A and on theobservation functional unit B. Or, a magnetic field smaller than themagnetic field strength Pth1 and greater than the magnetic fieldstrength Pth2 is emitted to turn on only the observation functional unitA, and then, a magnetic field greater than the magnetic field strengthPth1 is emitted to turn off the observation functional unit A and on theobservation functional unit B.

In other words, as shown in FIG. 58, in order to switch the currenton/off states of both of the observation functional units A, B, amagnetic field greater than the magnetic field strength Pth1 is emitted.In order to switch the current on/off states of the observationfunctional unit A, a magnetic field smaller than the magnetic fieldstrength Pth1 and greater than the magnetic field strength Pth2 isemitted. With use of the combination of these, desired on/off states canbe realized.

According to the system in the tenth embodiment, the on/off states ofthe plurality of observation functional units are independentlycontrolled by using a single magnetic field as a physical quantity.

The above-described magnetic sensors 403 a, 403 b are configured todetect magnetism with various magnetic field strengths; however, thepresent invention is not limited to this and, for example, magneticsensors having different resonance frequency may be employed, or, asshown in FIG. 59, a plurality of magnetic sensors may be arranged so asto detect magnetism in different directions.

Further, according the above-described system, a physical quantity isrealized as a magnetic field; however, the present invention is notlimited to this and an optical sensor, an X-ray sensor and the like maybe combined to control the on/off states independently. In this case,different physical quantity generating members are required if differentsensors are employed in combination.

According to the first to tenth embodiments, the on/off state control ofthe observation functional unit has mainly been explained; however, thepresent invention is not limited to this and it may be applied to anon/off state control of a plurality of functional units such as radiotransmission function, medicinal solution release function, markingfunction, bodily fluid/tissue sampling function, or operation armfunction. Obviously, it may be applied to system having a plurality ofsame functional units.

Further, according to the first to tenth embodiments, a magnetic field,light such as an infrared ray, and corpuscular ray such as X-ray aredescribed as examples of the physical quantity; however, the presentinvention is not limited to this and, for example, it may be applied tophysical quantities such as radio transmission and sound wave. Here, aphysical quantity detecting member in a capsule endoscope is assumed tohave a directivity to detect a physical quantity.

A case in which the intra-subject medical system including theabove-described capsule endoscope 2 is applied to an endoscopic surgicaloperation will be explained.

A first application example will be described. FIG. 60 is a flow chartshowing a procedure of a first application example of the intra-subjectmedical system applied to an endoscopic surgical operation. Firstly, thecapsule endoscope 2 is turned on and swallowed by a patient (step S501).Then, a site to be treated is specified in a real-time observation usingthe observation functional unit 12 (step S502). The capsule endoscope 2is turned off (step S503). Further a depressant is administrated to thepatient (step S504). This peristalsis depressant is administrated toprevent the capsule endoscope 2 from moving away from the specific siteby peristalsis.

Then, a preparation for an endoscopic surgical operation is performed(step S505), and when the preparation is completed, the capsuleendoscope 2 is turned on (step S506). An image from the capsuleendoscope and an image from a surgical endoscope are obtained and thedesired specific site is treated while monitoring the images (stepS507). Then, the procedure is completed.

Here, the endoscopic surgical operation is, as shown in FIG. 61, to forman abdominal cavity by introducing carbon dioxide into the patient bodyand to implement, in this condition, a surgical operation using anendoscope 511 or a forceps 510 and a surgical operation can be performedwith a small cut for forming a forcep hole 501 or the like. According tothe first application example, an image inside the digestive canal canbe monitored, more definitive treatment can be performed. Further, theelectricity consumption of the capsule endoscope 2 can be reduced. Asimilar effect may be obtained in general abdominal operations or thelike as well as the endoscopic surgical operation.

According to the first application example, a desired site is specifiedin a real-time observation in step S502; however, the present inventionis not limited to this and the desired site may be automaticallyspecified by implementing a predetermined image process on an obtainedimage. For example, when an image includes a larger red area, it may bedetermined as the desired site. After the desired site is specified, thecapsule endoscope 2 is automatically turned off by controlling themagnetic field generating unit 4.

Next, a second application example will be described. As shown in FIG.62, in the second application example, the capsule endoscope 2 is lockedby turning on a locking function unit of the capsule endoscope 2 (stepS604), as a substitute for administering a peristalsis depressant in thefirst application example (step S504). Other constituents, steps S601 toS603 and S605 to S607, are the same as steps S501 to S503 and S505 toS507 in FIG. 60.

Next a third application example will be described. As shown in the flowchart in FIG. 63, in the third application example, firstly, the capsuleendoscope 2 is turned off and swallowed by a patient (step S701). Then,the capsule endoscope 2 is moved to a desired site with use of a guidingmember and a position detecting member described in the aboveembodiments (step S702).

Here, the guiding member is, for example, to move the capsule endoscope2 in an axial direction 604 by adding a rotational magnetic field fromoutside the subject 1, while a spiral member 602 is provided around thecapsule endoscope 2 and a permanent magnet forming a magnetic fieldperpendicular to the axis of the capsule endoscope 2 is providedtherein, as shown in FIG. 64.

Then, a preparation for an endoscopic surgical operation is performed(step S703) and, when the preparation is completed, the capsuleendoscope 2 is turned on (step S704). Then, an image from the capsuleendoscope and an image from a surgical endoscope are obtained and thedesired specific site is treated while monitoring the obtained images(step S705). Then, the procedure is completed.

In the third application example, the power source energy of the capsuleendoscope 2 can be preserved since the capsule endoscope 2 is kept in anoff-state until the endoscopic surgical operation is started.

Next, a fourth application example will be described. In the fourthapplication example, two observation functional units are assumed to beincluded. As shown in the flow chart in FIG. 65, in the fourthapplication example, firstly only a first observation functional unit ofthe capsule endoscope 2 is turned on and the capsule endoscope 2 isswallowed by a patient (step S801). Then, a desired site is specified ina real-time observation using the first observation functional unit(step S802). A peristalsis depressant is administrated to the patient(step S803).

A preparation for an endoscopic surgical operation is performed (stepS804), and, when the preparation is completed, a second observationfunctional unit of the capsule endoscope 2 is turned on (step S805). Twoimages from the capsule endoscope and an image from a surgical endoscopeare obtained and the desired specific site is treated while monitoringthe images (step S806). Then, the procedure is completed.

Here, the transfer to the on-state of the second observation functionalunit is not limited to the above-described on/off state control and itmay be automatically implemented after the desired part is specified instep S802.

In the fourth application example, since images from the two observationfunctional units of the capsule endoscope 2 can be monitored during theendoscopic surgical operation, a broader view can be obtained andsecurer treatment can be performed.

Next, a fifth application example will be described. In the fifthapplication example, a treatment is performed using only the capsuleendoscope 2 and the capsule endoscope 2 is assumed to include treatmentfunction unit for biopsy function, medication function, hemostaticfunction, cauterization function, marking function and the like, inaddition to the observation functional unit.

In the fifth application example, as shown in the flow chart in FIG. 66,firstly, only the observation functional unit of the capsule endoscopeis turned on and the capsule endoscope is swallowed by a patient (stepS901). Then, a desired site to be treated is specified in a real-timeobservation using the observation functional unit in an on-state (stepS902). The treatment function unit of the capsule endoscope is turned on(step S903), and treatment is performed by the treatment function unitwhile performing a real-time observation (step S904). Then, theprocedure is completed.

In the fifth application example, since the observation functional unitor the treatment function unit are turned on for necessary observationor treatment, the observation or treatment can be performed with minimumenergy consumption.

Next, a sixth application example will be described. The sixthapplication example is a combination of the fifth application exampleand an endoscopic surgical operation.

In the sixth application example, as shown in the flow chart in FIG. 67,firstly, only the observation functional unit of the capsule endoscopeis turned on and the capsule endoscope is swallowed by a patient (stepS1001). A desired site to be treated is specified in a real-timeobservation using the observation functional unit in an on-state (stepS1002). Then a locking member in the capsule endoscope is turned on tolock the capsule endoscope (step S1003). Here, in step S1003, themovement of the capsule endoscope may be stopped by administeringperistalsis depressant.

The observation functional unit of the capsule endoscope is turned off(step S1004) and a preparation for an endoscopic surgical operation isperformed (step S1005). When the preparation is completed, theobservation functional unit of the capsule endoscope is turned on (stepS1006) and the treatment function unit of the capsule endoscope isturned on (step S1007).

An image from the capsule endoscope and an image from a surgicalendoscope are obtained and a treatment in association with a treatmentby the capsule endoscope and a treatment by the endoscopic surgicaloperation is performed while monitoring the images (step S1008). Then,the procedure is completed.

In the sixth application example, treatments are performed from insideand outside of the digestive canal so that more advanced treatment canbe performed.

In the above-described embodiments, an on/off state control of thebody-insertable device or an on/off state control of each function inthe body-insertable device is described. However, the effect of thepresent invention is not limited to such an on/off state control and maybe applied to, for example, an operation mode switching control of eachfunction (an input of a physical quantity triggers switching of theoperation mode). For example, regarding an observing function, everytime a predetermined physical quantity is applied, an observation speed(imaging flame rate) is switched from a high-speed mode used for theesophagus (e.g., 18 fps) to a medium-speed mode used for the stomach(e.g., 10 fps), and further, to a low-speed mode used for the smallintestine (e.g., 2 fps). Further, regarding a medication function,operation modes for dosage, medication cycle or the like may beswitched. Regarding the vital function, operation modes for amount ofbiopsies, cycle or the like may be switched. With this structure,operation modes of each function can be surely switched.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

1. A body-insertable device to be introduced into a subject, comprising:a magnetic field detecting member which has a directivity to detect amagnetic field; at least one functional member which has a necessaryfunction for examining or treating inside the subject; and a switchcontrol unit which controls an on/off states or operation mode of the atleast one functional member when the magnetic field detecting memberdetects a magnetic field, wherein the body-insertable device includes apermanent magnet so as to control a direction of the body-insertabledevice, according to a magnetic field generated outside the subject, andthe permanent magnet and the a magnetic field generating direction ofthe permanent magnet and the magnetic field detecting member arearranged such that a magnetic field generating direction of thepermanent magnet is perpendicular to a magnetism detecting direction ofthe magnetic field detecting member.
 2. The body-insertable deviceaccording to claim 1, wherein the magnetic field generating direction ofthe permanent magnet is perpendicular to an axial direction of thebody-insertable device, and the magnetism detecting direction of themagnetic field detecting member is in parallel to the axial direction.3. The body-insertable device according to claim 1, wherein when a firstmagnetic field generating member for emitting a temporal magnetic fieldinside the subject and a second magnetic field generating member forgenerating a magnetic field toward the subject in a predetermineddirection are arranged around the subject, the permanent magnetgenerates a force to move to a stable direction according to a polarityin the magnetic field in the predetermined direction, so that thedirection of the body-insertable device is controlled by the forcegenerated by the permanent magnet and the temporal magnetic field isemitted by the first magnetic field generating member in the directionin which the magnetic field detecting member has its directivity.
 4. Thebody-insertable device according to claim 1, wherein the functionalmember is at least one of an observing member for obtaining an image inthe subject, a radio member for performing radio transmission ofinformation of inside of the body-insertable device to outside thesubject, a medical solution release member for releasing medicalsolution in the subject, a marking member for marking a desired site inthe subject, a bodily fluid/tissue sampling member for sampling bodilyfluid or tissue in the subject, and an operation arm member forextending and contracting the arm in the subject.